In the future there will be billions and billions of old people. Bingo halls will outnumber night clubs, and hardly anyone will understand how email works.
The reason our population will be so geriatric-heavy is because scientists are getting pretty skilful at developing curative treatments for the diseases that used to kill us off before we turned 60. Our increasing lifespans would be fabulous news if it weren't for the fact that we’re a bit behind when it comes to treating age-related diseases of the brain.
Fitness is generating an enormous amount of interest amongst scientists, because its impact on the brain appears to be gigantic
The prospect of a wrinkly and senile future has led neuroscientists across the globe to turn their attentions towards ‘modifiable risk factors’ – i.e. lifestyle choices that we have control over – that influence how gracefully the human brain ages.
One study in older people already experiencing the first stages of dementia found that exercise could actually reverse some of their memory deficits
Some of these factors are obvious, such as smoking eventually blowing a large hole in your brain. Some, however, are more obscure: for example, learning a second language may delay the onset of dementia.
But one key risk factor – a person's fitness level – is generating an enormous amount of interest, primarily because its impact on the brain appears to be gigantic.
A recent study of 2,235 older men to see how fitness affects the brain, found that the risk of developing dementia was reduced by as much as 60% in those who'd followed a generally healthy lifestyle, with exercise being the leading mitigating factor.
Perhaps more significantly, a study of older people already experiencing the first stages of dementia found that exercise could actually reverse some of their memory deficits. Yet another study found that the hippocampus – the brain region responsible for memory – literally gets bigger after a program of moderate-intensity exercise.
However, before we all start campaigning for gym memberships to be available on the NHS, we need to know more about the types of exercise that are beneficial. Scientists have begun to answer this question, so here’s a summary of the evidence so far:
To determine whether aerobic exercise improves memory and increases the size of the hippocampus, a group of researchers at the University of Pittsburgh measured the brain region in 120 people before and after six months of either an aerobic or ‘stretching’ fitness program.
Sadly for those of us who were hoping that a bit of a stretch while watching telly would do the trick, the hippocampus of those in the aerobic group grew significantly more than in those in the stretching group, with associated improvements in their ability to perform memory tasks.
The evidence is less conclusive for yoga. While some studies comparing the impact of yoga on cognitive functions find no improvements compared to walking, others have found that yoga-based exercise has significant benefits. Most of these studies have been done in elderly people, however, and there are no well-controlled studies in people who have been practising long-term.
But, given the negative impact of stress on the brain, and the stress-busting effects of yoga, I would bet you a tenner that future studies in younger people find that yoga is a powerful means to maintain cognitive health as we age.
Undoubtedly, due to the cardiovascular element of most team sports, there will be benefits to cognitive health of being an active team member. However, choose your game carefully: athletes with a history of sports-related concussions have been found to eventually develop cognitive decline as they age.
Images acquired from the brains of these ex-athletes reveal microscopic structural injuries that are thought to interfere with the ability of different regions of the brain to communicate with each other, leading to poor cognitive performance. In short, if you’re looking for a team sport that’s good for your brain, maybe don’t go for rugby.